The overall objective of this project is to determine how herpes simplex virus (HSV) persists in cells which are either latently infected or which have become morphologically transformed as a consequence of an interaction. Specifically we wish to define which sequences of HSV-2 DNA code for products which are sufficient to alter the phenotype of cells; determine the arrangement of the viral sequences which are retained; and analyze the viral gene products. Additionally, we would like to determine whether expression of particular viral functions is necessary to maintain the HSV genome in a latent state in neurons.